Abstract

A hybrid integrated circuit (IC)/microfluidic chip is presented that independently and simultaneously traps and moves microscopic objects suspended in fluid using both electric and magnetic fields. This hybrid chip controls the location of dielectric objects, such as living cells and drops of fluid, on a 60 times 61 array of pixels that are 30 times 38 mum2 in size, each of which can be individually addressed with a 50-V peak-to-peak dc-to-10-MHz radio-frequency voltage. These high-voltage pixels produce electric fields above the chip's surface with a magnitude |oarrE| ap 1 V/ mum, resulting in strong dielectrophoresis (DEP) forces |oarrFDEP| ap 1 nN. Underneath the array of DEP pixels, there is a magnetic matrix that consists of two perpendicular sets of 60 metal wires running across the chip. Each wire can be sourced with 120 mA to trap and move magnetically susceptible objects using magnetophoresis. The DEP pixel array and magnetic matrix can be used simultaneously to apply forces to microscopic objects, such as living cells or lipid vesicles, that are tagged with magnetic nanoparticles. The capabilities of the hybrid IC/microfluidic chip demonstrated in this paper provide important building blocks for a platform for biological and chemical applications.